Low power mode

ABSTRACT

Examples of the disclosure are directed to a method of, after hitting a UVLO threshold, rebooting an electronic device in a low power mode having a lower UVLO threshold, such that the device can continue to be used past the first UVLO threshold. For example, in a high power mode, the device may be capable of a number of functionalities of a modern portable electronic device, such as network access, the ability to run applications, Bluetooth connections, etc. In a low power mode, the device may only be able to check and display a current time, play an alarm sound at a predefined time, perform near field communication (NFC) transactions/payments, among other possibilities described herein. The limited functionality and reduced usage of peripherals in the low power mode may prevent the battery from experiencing peaks in current level that may be problematic at relatively low levels of voltage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to and claims the benefit of U.S.Provisional Application Ser. No. 62/033,819, filed Aug. 6, 2014,entitled “Low Power Mode”, and to U.S. Provisional Application Ser. No.62/034,103, filed Aug. 6, 2014, entitled “Reduced-Size User Interfacesfor Battery Management,” the entire disclosure of which is hereinincorporated by reference in their entirety for all purposes.

FIELD OF THE DISCLOSURE

This relates generally to power management of an electronic device.

BACKGROUND OF THE DISCLOSURE

An electronic device may require a power supply, such as a battery.Further, the electronic device may require that the power supply have acertain minimum voltage in order to function properly. For example, abattery may not be able to sustain peaks in current level when thevoltage drops below a certain level. Accordingly, an electronic devicemay monitor the voltage of its power supply and power down when thevoltage falls below threshold.

SUMMARY OF THE DISCLOSURE

An electronic device may include a power supply, such as a battery. Ifthe electronic device is powered down, e.g., when the voltage falls toan undervoltage lockout (UVLO) threshold, a portion of the battery'scapacity may remain unused.

Examples of the disclosure are directed to a method of, after hitting avoltage threshold, such as an UVLO threshold, rebooting an electronicdevice in a low power mode having a different, lower UVLO threshold,such that the device can continue to be used. For example, in a highpower mode, the device may be capable of a number of functionalities ofa modern portable electronic device, such as network access, the abilityto run applications, Bluetooth connections, etc. In a low power mode,the device may be enabled for a limited set of functions. For example,the device may only be able to check and display a current time, play analarm sound at a predefined time, perform near field communication (NFC)transactions/payments, among other possibilities described herein. Thelimited functionality and reduced usage of peripherals in the low powermode may prevent the battery from experiencing peaks in current levelthat may be problematic at relatively low levels of voltage. Operationin a lower power mode also may extend the useful operation of anelectronic device. An electronic device may be any electronic devicesuch as a desktop computer, portable multifunction device (e.g., asmartphone), wearable device, tablet computer, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph illustrating an exemplary power discharge of anelectronic device, according to examples of the disclosure.

FIGS. 2A and 2B illustrate an exemplary method of managing a low powermode of an electronic device, according to examples of the disclosure.

FIG. 3 is a block diagram illustrating an exemplary API architecture,which may be used in some examples of the disclosure.

FIG. 4 illustrates an exemplary software stack of an API according toexamples of the disclosure.

FIG. 5 is a block diagram illustrating exemplary interactions betweenthe touch screen and other components of the device according toexamples of the disclosure.

FIG. 6 is a block diagram illustrating an example of a systemarchitecture that may be embodied within any portable or non-portabledevice according to examples of the disclosure.

DETAILED DESCRIPTION

In the following description of examples, reference is made to theaccompanying drawings which form a part hereof, and in which it is shownby way of illustration specific examples that can be practiced. It is tobe understood that other examples can be used and structural changes canbe made without departing from the scope of the disclosed examples.

Examples of the disclosure are directed to a method of, after hitting avoltage threshold, rebooting an electronic device in a low power modehaving a lower voltage threshold, such that the device can continue tobe used. An undervoltage lockout (UVLO) threshold is presented for thesake of example, but other and/or additional thresholds can be used. Forexample, in a high power mode, the device may be capable of a number offunctionalities of a modern portable electronic device, such as networkaccess, the ability to run applications, Bluetooth connections, etc. Ina low power mode, the device may only be able to perform a limited setof functions, e.g., check and display a current time, play an alarmsound at a predefined time, perform near field communication (NFC)transactions/payments, among other possibilities described herein. Thelimited functionality and reduced usage of peripherals in the low powermode may prevent the battery from experiencing peaks in current levelthat may be problematic at relatively low levels of voltage. Anelectronic device may be any electronic device such as a desktopcomputer, portable multifunction device (e.g., a smartphone), wearabledevice, tablet computer, etc.

FIG. 1 is a graph illustrating an exemplary power discharge of anelectronic device, according to examples of the disclosure. In thisexample, the electronic device may cease to function properly at a firstthreshold voltage level (104) (e.g., a high power mode UVLO level), 3.65volts (V). However, the 3.65 V level may be reached when the batterystill holds 10% of its charge capacity. Rather than let this chargecapacity go unused, examples of the disclosure describe a low powermode, with a reduced set of functionality, that can thereby function atlower voltage levels. This low power mode can have a lower UVLOthreshold (e.g., a low power mode UVLO level). For example, FIG. 1illustrates a low power mode UVLO threshold (106) of 3.10 V,corresponding to a 2% battery charge. In this example, enabling lowpower mode can allow usage of an additional 8% of the device's batterycharge. Further, the device may require a higher charge level before itre-enters high power mode from low power mode, so that in the high powermode the electronic device does not immediately encounter the firstthreshold again and the electronic device powers off. For example, FIG.1 illustrates a high power mode re-entry threshold (102) of 3.78 V,corresponding to an 18% battery charge.

In one example, a device may be used in a high power mode until thecharge reaches 10% (an example value of the first threshold describedbelow), at which point the device may reboot in low power mode. In thismode, the device may be used to display a current time (and otherlimited functionality). Then, if the device is recharged to at least 18%(an example value of the second threshold described below), then thedevice may reboot in the high power mode with all normal functionalityenabled. However, if the device continues to be used in the low powermode (e.g., to display a current time) until the charge reaches 2% (anexample value of the third threshold described below), the device maypower off completely (and be unable to power on until sufficientlyrecharged).

FIG. 2A illustrates an exemplary method of managing a low power mode ofan electronic device, according to examples of the disclosure. Themethod may be performed at an electronic device including a battery.

A first characteristic of the battery (e.g., a voltage level, a chargelevel, or some other measure that may relate to the remaining capacityof the battery) may be obtained (201), and it may be determined (203)whether the first characteristic is lower than a first threshold (e.g.,an undervoltage-lockout (UVLO) threshold).

In accordance with a determination that the first characteristic ishigher than the first threshold, a high power mode may be maintained(225). In accordance with a determination that the first characteristicis lower than the first threshold, a low power mode may be enabled(e.g., by setting a low power mode flag) (205). In some examples,enabling the low power mode may include setting a low power mode flagbefore powering off or rebooting the electronic device, storing a localtime offset (e.g., an offset from coordinated universal time (UTC)), andstoring an alarm time. Further, in some examples, in the low power mode,a current time may be obtained, the local time offset may be applied tothe current time to obtain a local time, and the local time may bedisplayed. It may be determined that the current time is the alarm time,and, in accordance with a determination that the current time is thealarm time, an alarm sound may be played, the display may indicate thatan alarm is going off, and/or the device may vibrate.

In some examples, enabling the low power mode may include storingauthorization information for performing NFC transactions/payments(e.g., storing encryption keys, credit card numbers, passwords, etc.).Further, in some examples, in the low power mode, an NFC module maycommunicate some or all of the authorization information to perform orreceive a mobile payment.

A booting process may be initiated (207) (e.g., a booting process may beinitiated following a reboot or power cycle of the electronic device;the electronic device may force a power off and/or reboot in accordancewith a determination that the first characteristic is lower than thefirst threshold). For example, after a reboot or power cycle, the devicemay initialize itself and load a boot loader, which, in some examples,may then load either a low power mode firmware image or a high powermode firmware image (as discussed below with reference to 215 and 217).

As part of the booting process, a second characteristic of the batterymay be obtained (211) (e.g., a voltage level, a charge level, or someother measure that may relate to the remaining capacity of the battery).It may be determined whether the second characteristic is lower than asecond threshold (213) (e.g., a UVLO threshold or a threshold higherthan the UVLO threshold). In some examples, the second threshold may bedifferent from the first threshold (e.g., higher, so that in the highpower mode the electronic device does not immediately encounter thefirst threshold again and the electronic device powers off).

In accordance with a determination that the second characteristic islower than the second threshold, the electronic device may continue thebooting process according to the low power mode (215). For example, theboot loader may load a firmware image corresponding to the low powermode. In some examples, the low power mode firmware image may onlyenable certain functionality/drivers (e.g., displaying time) and otherdrivers are not loaded (e.g., the low power mode firmware image mayinclude an operating system having relatively limited functionality, asfurther described below). In accordance with a determination that thesecond characteristic is higher than the second threshold, theelectronic device may continue the booting process according to a highpower mode (217). For example, the boot loader may load a firmware imagecorresponding to the high power mode (e.g., a high power mode firmwareimage may include an operating system having relatively expansivefunctionality compared to an operating system of a low power modefirmware image, as further described below).

In some examples, in the low power mode, only a subset of modules of theelectronic device may be powered on (e.g., only powering on the display,touch controller, central processing unit (CPU), near fieldcommunications (NFC), and/or speaker, among other possibilities).Further, in the high power mode, the subset of modules of the electronicdevice and on one or more additional modules of the electronic device(e.g., graphics processing unit (GPU), microphone, Wi-Fi controller,Bluetooth, accelerometer, gyroscope, magnetometer, etc.) may be poweredon.

In some examples, the low power mode does not allow the device to bootin the operating system that would execute in the high power mode. Forexample, in the high power mode, a first operating system having aplurality of functionalities (e.g., multitasking, network access, etc.)may be invoked. In the low power mode, a second operating system havingonly a subset of the plurality of functionalities of the first operatingsystem (e.g., displaying a current time, playing an alarm sound when thecurrent time is an alarm time, using NFC, among other possibilities) maybe invoked.

FIG. 2B illustrates an exemplary method of managing a low power mode ofan electronic device, according to examples of the disclosure. In someexamples, in the low power mode, a third characteristic of the batterymay be obtained (219) (e.g., a voltage level, a charge level, or someother measure that may relate to the remaining capacity of the battery).It may be determined whether the third characteristic is lower than athird threshold (221) (e.g., a different UVLO threshold for the lowpower mode, lower than the initial UVLO threshold). In accordance with adetermination that the third characteristic is lower than the thirdthreshold, the device may be powered off (223). In accordance with adetermination that the third characteristic is higher than the thirdthreshold, power to the electronic device may be maintained (227).

In an illustrative example, an electronic device is used until thebattery level falls below 10%. In response to the battery level fallingbelow 10%, the device powers off, ready to be booted in the low powermode. When a user presses a button or otherwise interacts with thedevice (e.g., to check the time), the device boots in the low powermode, displays the time, and then powers off. The user charges thedevice to 15%, then presses a button on the device, the device againboots in the low power mode. However, once the device is charged above18% and the user presses a button on the device, the device boots in thehigh power mode and additional functionality is restored.

In some examples, instead of powering off, the electronic device mayautomatically reboot in the low power mode in response to the batterylevel falling below 10% (without further user interaction). The devicemay remain powered on in the low power mode until the charge goes above18%, at which point the device automatically reboots in the high powermode (without further user interaction).

The examples discussed above can be implemented in one or moreApplication Programming Interfaces (APIs). An API is an interfaceimplemented by a program code component or hardware component(hereinafter “API-implementing component”) that allows a differentprogram code component or hardware component (hereinafter “API-callingcomponent”) to access and use one or more functions, methods,procedures, data structures, classes, and/or other services provided bythe API-implementing component. An API can define one or more parametersthat are passed between the API-calling component and theAPI-implementing component.

The above-described features can be implemented as part of anapplication program interface (API) that can allow it to be incorporatedinto different applications (e.g., spreadsheet apps) utilizing touchinput as an input mechanism. An API can allow a developer of anAPI-calling component (which may be a third party developer) to leveragespecified features, such as those described above, provided by anAPI-implementing component. There may be one API-calling component orthere may be more than one such component. An API can be a source codeinterface that a computer system or program library provides in order tosupport requests for services from an application. An operating system(OS) can have multiple APIs to allow applications running on the OS tocall one or more of those APIs, and a service (such as a programlibrary) can have multiple APIs to allow an application that uses theservice to call one or more of those APIs. An API can be specified interms of a programming language that can be interpreted or compiled whenan application is built.

In some examples, the API-implementing component may provide more thanone API, each providing a different view of the functionalityimplemented by the API-implementing component, or with different aspectsthat access different aspects of the functionality implemented by theAPI-implementing component. For example, one API of an API-implementingcomponent can provide a first set of functions and can be exposed tothird party developers, and another API of the API-implementingcomponent can be hidden (not exposed) and provide a subset of the firstset of functions and also provide another set of functions, such astesting or debugging functions which are not in the first set offunctions. In other examples the API-implementing component may itselfcall one or more other components via an underlying API and thus be bothan API-calling component and an API-implementing component.

An API defines the language and parameters that API-calling componentsuse when accessing and using specified features of the API-implementingcomponent. For example, an API-calling component accesses the specifiedfeatures of the API-implementing component through one or more API callsor invocations (embodied for example by function or method calls)exposed by the API and passes data and control information usingparameters via the API calls or invocations. The API-implementingcomponent may return a value through the API in response to an API callfrom an API-calling component. While the API defines the syntax andresult of an API call (e.g., how to invoke the API call and what the APIcall does), the API may not reveal how the API call accomplishes thefunction specified by the API call. Various API calls are transferredvia the one or more application programming interfaces between thecalling (API-calling component) and an API-implementing component.Transferring the API calls may include issuing, initiating, invoking,calling, receiving, returning, or responding to the function calls ormessages; in other words, transferring can describe actions by either ofthe API-calling component or the API-implementing component. Thefunction calls or other invocations of the API may send or receive oneor more parameters through a parameter list or other structure. Aparameter can be a constant, key, data structure, object, object class,variable, data type, pointer, array, list or a pointer to a function ormethod or another way to reference a data or other item to be passed viathe API.

Furthermore, data types or classes may be provided by the API andimplemented by the API-implementing component. Thus, the API-callingcomponent may declare variables, use pointers to, use or instantiateconstant values of such types or classes by using definitions providedin the API.

Generally, an API can be used to access a service or data provided bythe API-implementing component or to initiate performance of anoperation or computation provided by the API-implementing component. Byway of example, the API-implementing component and the API-callingcomponent may each be any one of an operating system, a library, adevice driver, an API, an application program, or other module (itshould be understood that the API-implementing component and theAPI-calling component may be the same or different type of module fromeach other). API-implementing components may in some cases be embodiedat least in part in firmware, microcode, or other hardware logic. Insome examples, an API may allow a client program to use the servicesprovided by a Software Development Kit (SDK) library. In other examplesan application or other client program may use an API provided by anApplication Framework. In these examples the application or clientprogram may incorporate calls to functions or methods provided by theSDK and provided by the API or use data types or objects defined in theSDK and provided by the API. An Application Framework may in theseexamples provide a main event loop for a program that responds tovarious events defined by the Framework. The API allows the applicationto specify the events and the responses to the events using theApplication Framework. In some implementations, an API call can reportto an application the capabilities or state of a hardware device,including those related to aspects such as input capabilities and state,output capabilities and state, processing capability, power state,storage capacity and state, communications capability, etc., and the APImay be implemented in part by firmware, microcode, or other low levellogic that executes in part on the hardware component.

The API-calling component may be a local component (i.e., on the samedata processing system as the API-implementing component) or a remotecomponent (i.e., on a different data processing system from theAPI-implementing component) that communicates with the API-implementingcomponent through the API over a network. It should be understood thatan API-implementing component may also act as an API-calling component(i.e., it may make API calls to an API exposed by a differentAPI-implementing component) and an API-calling component may also act asan API-implementing component by implementing an API that is exposed toa different API-calling component.

The API may allow multiple API-calling components written in differentprogramming languages to communicate with the API-implementing component(thus the API may include features for translating calls and returnsbetween the API-implementing component and the API-calling component);however the API may be implemented in terms of a specific programminglanguage. An API-calling component can, in one example, call APIs fromdifferent providers such as a set of APIs from an OS provider andanother set of APIs from a plug-in provider and another set of APIs fromanother provider (e.g. the provider of a software library) or creator ofthe another set of APIs.

FIG. 3 is a block diagram illustrating an exemplary API architecture,which may be used in some examples of the disclosure. As shown in FIG.3, the API architecture 600 includes the API-implementing component 610(e.g., an operating system, a library, a device driver, an API, anapplication program, software or other module) that implements the API620. The API 620 specifies one or more functions, methods, classes,objects, protocols, data structures, formats and/or other features ofthe API-implementing component that may be used by the API-callingcomponent 630. The API 620 can specify at least one calling conventionthat specifies how a function in the API-implementing component receivesparameters from the API-calling component and how the function returns aresult to the API-calling component. The API-calling component 630(e.g., an operating system, a library, a device driver, an API, anapplication program, software or other module), makes API calls throughthe API 620 to access and use the features of the API-implementingcomponent 610 that are specified by the API 620. The API-implementingcomponent 610 may return a value through the API 620 to the API-callingcomponent 630 in response to an API call.

It will be appreciated that the API-implementing component 610 mayinclude additional functions, methods, classes, data structures, and/orother features that are not specified through the API 620 and are notavailable to the API-calling component 630. It should be understood thatthe API-calling component 630 may be on the same system as theAPI-implementing component 610 or may be located remotely and accessesthe API-implementing component 610 using the API 620 over a network.While FIG. 3 illustrates a single API-calling component 630 interactingwith the API 620, it should be understood that other API-callingcomponents, which may be written in different languages (or the samelanguage) than the API-calling component 630, may use the API 620.

The API-implementing component 610, the API 620, and the API-callingcomponent 630 may be stored in a non-transitory machine-readable storagemedium, which includes any mechanism for storing information in a formreadable by a machine (e.g., a computer or other data processingsystem). For example, a machine-readable medium includes magnetic disks,optical disks, random access memory; read only memory, flash memorydevices, etc.

In the exemplary software stack shown in FIG. 4, applications can makecalls to Services A or B using several Service APIs and to OperatingSystem (OS) using several OS APIs. Services A and B can make calls to OSusing several OS APIs.

Note that the Service 2 has two APIs, one of which (Service 2 API 1)receives calls from and returns values to Application 1 and the other(Service 2 API 2) receives calls from and returns values to Application2. Service 1 (which can be, for example, a software library) makes callsto and receives returned values from OS API 1, and Service 2 (which canbe, for example, a software library) makes calls to and receivesreturned values from both OS API 1 and OS API 2. Application 2 makescalls to and receives returned values from OS API 2.

FIG. 5 is a block diagram illustrating exemplary interactions betweenthe touch screen and the other components of the device. Describedexamples may include touch I/O device 1001 that can receive touch inputfor interacting with computing system 1003 via wired or wirelesscommunication channel 1002. Touch I/O device 1001 may be used to provideuser input to computing system 1003 in lieu of or in combination withother input devices such as a keyboard, mouse, etc. One or more touchI/O devices 1001 may be used for providing user input to computingsystem 1003. Touch I/O device 1001 may be an integral part of computingsystem 1003 (e.g., touch screen on a smartphone or a tablet PC) or maybe separate from computing system 1003.

Touch I/O device 1001 may include a touch sensing panel which is whollyor partially transparent, semitransparent, non-transparent, opaque orany combination thereof. Touch I/O device 1001 may be embodied as atouch screen, touch pad, a touch screen functioning as a touch pad(e.g., a touch screen replacing the touchpad of a laptop), a touchscreen or touchpad combined or incorporated with any other input device(e.g., a touch screen or touchpad disposed on a keyboard) or anymulti-dimensional object having a touch sensing surface for receivingtouch input.

In one example, touch I/O device 1001 embodied as a touch screen mayinclude a transparent and/or semitransparent touch sensing panelpartially or wholly positioned over at least a portion of a display.According to this example, touch I/O device 1001 functions to displaygraphical data transmitted from computing system 1003 (and/or anothersource) and also functions to receive user input. In other examples,touch I/O device 1001 may be embodied as an integrated touch screenwhere touch sensing components/devices are integral with displaycomponents/devices. In still other examples a touch screen may be usedas a supplemental or additional display screen for displayingsupplemental or the same graphical data as a primary display and toreceive touch input.

Touch I/O device 1001 may be configured to detect the location of one ormore touches or near touches on device 1001 based on capacitive,resistive, optical, acoustic, inductive, mechanical, chemicalmeasurements, or any phenomena that can be measured with respect to theoccurrences of the one or more touches or near touches in proximity todevice 1001. Software, hardware, firmware or any combination thereof maybe used to process the measurements of the detected touches to identifyand track one or more gestures. A gesture may correspond to stationaryor non-stationary, single or multiple, touches or near touches on touchI/O device 1001. A gesture may be performed by moving one or morefingers or other objects in a particular manner on touch I/O device 1001such as tapping, pressing, rocking, scrubbing, twisting, changingorientation, pressing with varying pressure and the like at essentiallythe same time, contiguously, or consecutively. A gesture may becharacterized by, but is not limited to a pinching, sliding, swiping,rotating, flexing, dragging, or tapping motion between or with any otherfinger or fingers. A single gesture may be performed with one or morehands, by one or more users, or any combination thereof.

Computing system 1003 may drive a display with graphical data to displaya graphical user interface (GUI). The GUI may be configured to receivetouch input via touch I/O device 1001. Embodied as a touch screen, touchI/O device 1001 may display the GUI. Alternatively, the GUI may bedisplayed on a display separate from touch I/O device 1001. The GUI mayinclude graphical elements displayed at particular locations within theinterface. Graphical elements may include but are not limited to avariety of displayed virtual input devices including virtual scrollwheels, a virtual keyboard, virtual knobs, virtual buttons, any virtualUI, and the like. A user may perform gestures at one or more particularlocations on touch I/O device 1001 which may be associated with thegraphical elements of the GUI. In other examples, the user may performgestures at one or more locations that are independent of the locationsof graphical elements of the GUI. Gestures performed on touch I/O device1001 may directly or indirectly manipulate, control, modify, move,actuate, initiate or generally affect graphical elements such ascursors, icons, media files, lists, text, all or portions of images, orthe like within the GUI. For instance, in the case of a touch screen, auser may directly interact with a graphical element by performing agesture over the graphical element on the touch screen. Alternatively, atouch pad generally provides indirect interaction. Gestures may alsoaffect non-displayed GUI elements (e.g., causing user interfaces toappear) or may affect other actions within computing system 1003 (e.g.,affect a state or mode of a GUI, application, or operating system).Gestures may or may not be performed on touch I/O device 1001 inconjunction with a displayed cursor. For instance, in the case in whichgestures are performed on a touchpad, a cursor (or pointer) may bedisplayed on a display screen or touch screen and the cursor may becontrolled via touch input on the touchpad to interact with graphicalobjects on the display screen. In other examples in which gestures areperformed directly on a touch screen, a user may interact directly withobjects on the touch screen, with or without a cursor or pointer beingdisplayed on the touch screen.

Feedback may be provided to the user via communication channel 1002 inresponse to or based on the touch or near touches on touch I/O device1001. Feedback may be transmitted optically, mechanically, electrically,olfactory, acoustically, or the like or any combination thereof and in avariable or non-variable manner.

Attention is now directed towards examples of a system architecture thatmay be embodied within any portable or non-portable device including butnot limited to a communication device (e.g. mobile phone, smart phone),a multi-media device (e.g., MP3 player, TV, radio), a portable orhandheld computer (e.g., tablet, netbook, laptop), a desktop computer,an All-In-One desktop, a peripheral device, or any other system ordevice adaptable to the inclusion of system architecture 2000, includingcombinations of two or more of these types of devices. FIG. 6 is a blockdiagram of one example of system 2000 that generally includes one ormore computer-readable mediums 2001, processing system 2004, I/Osubsystem 2006, radio frequency (RF) circuitry 2008, audio circuitry2010, and sensors circuitry 2011. These components may be coupled by oneor more communication buses or signal lines 2003.

It should be apparent that the architecture shown in FIG. 6 is only oneexample architecture of system 2000, and that system 2000 could havemore or fewer components than shown, or a different configuration ofcomponents. The various components shown in FIG. 6 can be implemented inhardware, software, firmware or any combination thereof, including oneor more signal processing and/or application specific integratedcircuits.

RF circuitry 2008 can be used to send and receive information over awireless link or network to one or more other devices and includeswell-known circuitry for performing this function. RF circuitry 2008 andaudio circuitry 2010 can be coupled to processing system 2004 viaperipherals interface 2016. Interface 2016 can include various knowncomponents for establishing and maintaining communication betweenperipherals and processing system 2004. Audio circuitry 2010 can becoupled to audio speaker 2050 and microphone 2052 and can include knowncircuitry for processing voice signals received from interface 2016 toenable a user to communicate in real-time with other users. In someexamples, audio circuitry 2010 can include a headphone jack (not shown).Sensors circuitry 2011 can be coupled to various sensors including, butnot limited to, one or more Light Emitting Diodes (LEDs) or other lightemitters, one or more photodiodes or other light sensors, one or morephotothermal sensors, a magnetometer, an accelerometer, a gyroscope, abarometer, a compass, a proximity sensor, a camera, an ambient lightsensor, a thermometer, a GPS sensor, and various system sensors whichcan sense remaining battery life, power consumption, processor speed,CPU load, and the like.

Peripherals interface 2016 can couple the input and output peripheralsof the system to processor 2018 and computer-readable medium 2001. Oneor more processors 2018 communicate with one or more computer-readablemediums 2001 via controller 2020. Computer-readable medium 2001 can beany device or medium that can store code and/or data for use by one ormore processors 2018. In some examples, medium 2001 can be anon-transitory computer-readable storage medium. Medium 2001 can includea memory hierarchy, including but not limited to cache, main memory andsecondary memory. The memory hierarchy can be implemented using anycombination of RAM (e.g., SRAM, DRAM, DDRAM), ROM, FLASH, magneticand/or optical storage devices, such as disk drives, magnetic tape, CDs(compact disks) and DVDs (digital video discs). Medium 2001 may alsoinclude a transmission medium for carrying information-bearing signalsindicative of computer instructions or data (with or without a carrierwave upon which the signals are modulated). For example, thetransmission medium may include a communications network, including butnot limited to the Internet (also referred to as the World Wide Web),intranet(s), Local Area Networks (LANs), Wide Local Area Networks(WLANs), Storage Area Networks (SANs), Metropolitan Area Networks (MAN)and the like.

One or more processors 2018 can run various software components storedin medium 2001 to perform various functions for system 2000. In someexamples, the software components can include operating system 2022,communication module (or set of instructions) 2024, touch processingmodule (or set of instructions) 2026, graphics module (or set ofinstructions) 2028, and one or more applications (or set ofinstructions) 2030. Each of these modules and above noted applicationscan correspond to a set of instructions for performing one or morefunctions described above and the methods described in this application(e.g., the computer-implemented methods and other information processingmethods described herein). These modules (i.e., sets of instructions)need not be implemented as separate software programs, procedures ormodules, and thus various subsets of these modules may be combined orotherwise re-arranged in various examples. In some examples, medium 2001may store a subset of the modules and data structures identified above.Furthermore, medium 2001 may store additional modules and datastructures not described above.

Operating system 2022 can include various procedures, sets ofinstructions, software components and/or drivers for controlling andmanaging general system tasks (e.g., memory management, storage devicecontrol, power management, etc.) and facilitates communication betweenvarious hardware and software components.

Communication module 2024 can facilitate communication with otherdevices over one or more external ports 2036 or via RF circuitry 2008and can include various software components for handling data receivedfrom RF circuitry 2008 and/or external port 2036.

Graphics module 2028 can include various known software components forrendering, animating and displaying graphical objects on a displaysurface. In examples in which touch I/O device 2012 is a touch sensingdisplay (e.g., touch screen), graphics module 2028 can includecomponents for rendering, displaying, and animating objects on the touchsensing display.

One or more applications 2030 can include any applications installed onsystem 2000, including without limitation, a browser, address book,contact list, email, instant messaging, word processing, keyboardemulation, widgets, JAVA-enabled applications, encryption, digitalrights management, voice recognition, voice replication, locationdetermination capability (such as that provided by the globalpositioning system (GPS)), a music player, etc.

Touch processing module 2026 can include various software components forperforming various tasks associated with touch I/O device 2012 includingbut not limited to receiving and processing touch input received fromI/O device 2012 via touch I/O device controller 2032.

I/O subsystem 2006 can be coupled to touch I/O device 2012 and one ormore other I/O devices 2014 for controlling or performing variousfunctions. Touch I/O device 2012 can communicate with processing system2004 via touch I/O device controller 2032, which can include variouscomponents for processing user touch input (e.g., scanning hardware).One or more other input controllers 2034 can receive/send electricalsignals from/to other I/O devices 2014. Other I/O devices 2014 mayinclude physical buttons, dials, slider switches, sticks, keyboards,touch pads, additional display screens, or any combination thereof.

If embodied as a touch screen, touch I/O device 2012 can display visualoutput to the user in a GUI. The visual output may include text,graphics, video, and any combination thereof. Some or all of the visualoutput may correspond to user-interface objects. Touch I/O device 2012can form a touch sensing surface that accepts touch input from the user.Touch I/O device 2012 and touch screen controller 2032 (along with anyassociated modules and/or sets of instructions in medium 2001) candetect and track touches or near touches (and any movement or release ofthe touch) on touch I/O device 2012 and can convert the detected touchinput into interaction with graphical objects, such as one or moreuser-interface objects. In the case in which device 2012 is embodied asa touch screen, the user can directly interact with graphical objectsthat are displayed on the touch screen. Alternatively, in the case inwhich device 2012 is embodied as a touch device other than a touchscreen (e.g., a touch pad), the user may indirectly interact withgraphical objects that are displayed on a separate display screenembodied as I/O device 2014.

Touch I/O device 2012 may be analogous to the multi-touch sensingsurface described in the following U.S. Pat. No. 6,323,846 (Westerman etal.), U.S. Pat. No. 6,570,557 (Westerman et al.), and/or U.S. Pat. No.6,677,932 (Westerman), and/or U.S. Patent Publication 2002/0015024A1,each of which is hereby incorporated by reference.

In examples for which touch I/O device 2012 is a touch screen, the touchscreen may use LCD (liquid crystal display) technology, LPD (lightemitting polymer display) technology, OLED (organic LED), or OEL(organic electro luminescence), although other display technologies maybe used in other examples.

Feedback may be provided by touch I/O device 2012 based on the user'stouch input as well as a state or states of what is being displayedand/or of the computing system. Feedback may be transmitted optically(e.g., light signal or displayed image), mechanically (e.g., hapticfeedback, touch feedback, force feedback, or the like), electrically(e.g., electrical stimulation), olfactory, acoustically (e.g., beep orthe like), or the like or any combination thereof and in a variable ornon-variable manner.

System 2000 can also include power system 2044 for powering the varioushardware components and may include a power management system, one ormore power sources, a recharging system, a power failure detectioncircuit, a power converter or inverter, a power status indicator and anyother components typically associated with the generation, managementand distribution of power in portable devices.

In some examples, peripherals interface 2016, one or more processors2018, and memory controller 2020 may be implemented on a single chip,such as processing system 2004. In some other examples, they may beimplemented on separate chips.

Examples of the disclosure can be advantageous in enabling a low powermode with a UVLO threshold lower than the UVLO threshold in the highpower mode, thereby allowing the device to be used for a longer periodof time.

In some examples, a method of an electronic device including a batteryis disclosed. The method may include: obtaining a first characteristicof the battery; determining that the first characteristic is lower thana first threshold; in accordance with a determination that the firstcharacteristic is lower than the first threshold, enabling a low powermode; initiating a booting process; obtaining a second characteristic ofthe battery; determining whether the second characteristic is lower thana second threshold; in accordance with a determination that the secondcharacteristic is lower than the second threshold, continuing thebooting process according to the low power mode; and in accordance witha determination that the second characteristic is higher than the secondthreshold, continuing the booting process according to a high powermode. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode, onlypowering on a subset of modules of the electronic device; and in thehigh power mode, powering on the subset of modules of the electronicdevice and powering on one or more additional modules of the electronicdevice. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the high power mode,invoking a first operating system having a plurality of functionalities;and in the low power mode, invoking a second operating system havingonly a subset of the plurality of functionalities of the first operatingsystem. Additionally or alternatively to one or more of the aboveexamples, enabling the low power mode may include: setting a low powermode flag before initiating the booting process; storing a local timeoffset; and storing an alarm time. Additionally or alternatively to oneor more of the above examples, the method may further include, in thelow power mode: obtaining a current time; applying the local time offsetto the current time to obtain a local time; and displaying the localtime. Additionally or alternatively to one or more of the aboveexamples, the method may further include, in the low power mode:determining that a current time is the alarm time; and in accordancewith a determination that the current time is the alarm time, playing analarm sound. Additionally or alternatively to one or more of the aboveexamples, the second threshold may be different from the firstthreshold. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode,obtaining a third characteristic of the battery; determining that thethird characteristic is lower than a third threshold; and in accordancewith a determination that the third characteristic is lower than thethird threshold, powering off the device.

In some examples, a non-transitory computer readable storage mediumstoring one or more programs is disclosed. The one or more programs mayinclude instructions, which when executed by an electronic deviceincluding a battery, cause the electronic device to perform a methodincluding: obtaining a first characteristic of the battery; determiningthat the first characteristic is lower than a first threshold; inaccordance with a determination that the first characteristic is lowerthan the first threshold, enabling a low power mode; initiating abooting process; obtaining a second characteristic of the battery;determining whether the second characteristic is lower than a secondthreshold; in accordance with a determination that the secondcharacteristic is lower than the second threshold, continuing thebooting process according to the low power mode; and in accordance witha determination that the second characteristic is higher than the secondthreshold, continuing the booting process according to a high powermode. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode, onlypowering on a subset of modules of the electronic device; and in thehigh power mode, powering on the subset of modules of the electronicdevice and powering on one or more additional modules of the electronicdevice. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the high power mode,invoking a first operating system having a plurality of functionalities;and in the low power mode, invoking a second operating system havingonly a subset of the plurality of functionalities of the first operatingsystem. Additionally or alternatively to one or more of the aboveexamples, enabling the low power mode may include: setting a low powermode flag before initiating the booting process; storing a local timeoffset; and storing an alarm time. Additionally or alternatively to oneor more of the above examples, the method may further include, in thelow power mode: obtaining a current time; applying the local time offsetto the current time to obtain a local time; and displaying the localtime. Additionally or alternatively to one or more of the aboveexamples, the method may further include, in the low power mode:determining that a current time is the alarm time; and in accordancewith a determination that the current time is the alarm time, playing analarm sound. Additionally or alternatively to one or more of the aboveexamples, the second threshold may be different from the firstthreshold. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode,obtaining a third characteristic of the battery; determining that thethird characteristic is lower than a third threshold; and in accordancewith a determination that the third characteristic is lower than thethird threshold, powering off the device.

In some examples, an electronic device is disclosed. The electronicdevice may include: one or more processors; memory; a battery; and oneor more programs, wherein the one or more programs may be stored in thememory and configured to be executed by the one or more processors,which when executed by the one or more processors, cause the electronicdevice to perform a method including: obtaining a first characteristicof the battery; determining that the first characteristic is lower thana first threshold; in accordance with a determination that the firstcharacteristic is lower than the first threshold, enabling a low powermode; initiating a booting process; obtaining a second characteristic ofthe battery; determining whether the second characteristic is lower thana second threshold; in accordance with a determination that the secondcharacteristic is lower than the second threshold, continuing thebooting process according to the low power mode; and in accordance witha determination that the second characteristic is higher than the secondthreshold, continuing the booting process according to a high powermode. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode, onlypowering on a subset of modules of the electronic device; and in thehigh power mode, powering on the subset of modules of the electronicdevice and powering on one or more additional modules of the electronicdevice. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the high power mode,invoking a first operating system having a plurality of functionalities;and in the low power mode, invoking a second operating system havingonly a subset of the plurality of functionalities of the first operatingsystem. Additionally or alternatively to one or more of the aboveexamples, enabling the low power mode may include: setting a low powermode flag before initiating the booting process; storing a local timeoffset; and storing an alarm time. Additionally or alternatively to oneor more of the above examples, the method may further include, in thelow power mode: obtaining a current time; applying the local time offsetto the current time to obtain a local time; and displaying the localtime. Additionally or alternatively to one or more of the aboveexamples, the method may further include, in the low power mode:determining that a current time is the alarm time; and in accordancewith a determination that the current time is the alarm time, playing analarm sound. Additionally or alternatively to one or more of the aboveexamples, the second threshold may be different from the firstthreshold. Additionally or alternatively to one or more of the aboveexamples, the method may further include: in the low power mode,obtaining a third characteristic of the battery; determining that thethird characteristic is lower than a third threshold; and in accordancewith a determination that the third characteristic is lower than thethird threshold, powering off the device.

Although the disclosed examples have been fully described with referenceto the accompanying drawings, it is to be noted that various changes andmodifications will become apparent to those skilled in the art. Suchchanges and modifications are to be understood as being included withinthe scope of the disclosed examples as defined by the appended claims.

What is claimed is:
 1. A method of an electronic device including abattery, the method comprising: obtaining a first characteristic of thebattery; determining that the first characteristic is lower than a firstthreshold; in accordance with a determination that the firstcharacteristic is lower than the first threshold, enabling a low powermode; initiating a booting process; obtaining a second characteristic ofthe battery; determining whether the second characteristic is lower thana second threshold; in accordance with a determination that the secondcharacteristic is lower than the second threshold, continuing thebooting process according to the low power mode; and in accordance witha determination that the second characteristic is higher than the secondthreshold, continuing the booting process according to a high powermode.
 2. The method of claim 1, the method further comprising: in thelow power mode, only powering on a subset of modules of the electronicdevice; and in the high power mode, powering on the subset of modules ofthe electronic device and powering on one or more additional modules ofthe electronic device.
 3. The method of claim 1, the method furthercomprising: in the high power mode, invoking a first operating systemhaving a plurality of functionalities; and in the low power mode,invoking a second operating system having only a subset of the pluralityof functionalities of the first operating system.
 4. The method of claim1, wherein enabling the low power mode includes: setting a low powermode flag before initiating the booting process; storing a local timeoffset; and storing an alarm time.
 5. The method of claim 4, the methodfurther comprising, in the low power mode: obtaining a current time;applying the local time offset to the current time to obtain a localtime; and displaying the local time.
 6. The method of claim 4, themethod further comprising, in the low power mode: determining that acurrent time is the alarm time; and in accordance with a determinationthat the current time is the alarm time, playing an alarm sound.
 7. Themethod of claim 1, wherein the second threshold is different from thefirst threshold.
 8. The method of claim 1, the method furthercomprising: in the low power mode, obtaining a third characteristic ofthe battery; determining that the third characteristic is lower than athird threshold; and in accordance with a determination that the thirdcharacteristic is lower than the third threshold, powering off thedevice.
 9. A non-transitory computer readable storage medium storing oneor more programs, the one or more programs comprising instructions,which when executed by an electronic device including a battery, causethe electronic device to perform a method comprising: obtaining a firstcharacteristic of the battery; determining that the first characteristicis lower than a first threshold; in accordance with a determination thatthe first characteristic is lower than the first threshold, enabling alow power mode; initiating a booting process; obtaining a secondcharacteristic of the battery; determining whether the secondcharacteristic is lower than a second threshold; in accordance with adetermination that the second characteristic is lower than the secondthreshold, continuing the booting process according to the low powermode; and in accordance with a determination that the secondcharacteristic is higher than the second threshold, continuing thebooting process according to a high power mode.
 10. The non-transitorycomputer readable storage medium of claim 9, the method furthercomprising: in the low power mode, only powering on a subset of modulesof the electronic device; and in the high power mode, powering on thesubset of modules of the electronic device and powering on one or moreadditional modules of the electronic device.
 11. The non-transitorycomputer readable storage medium of claim 9, the method furthercomprising: in the high power mode, invoking a first operating systemhaving a plurality of functionalities; and in the low power mode,invoking a second operating system having only a subset of the pluralityof functionalities of the first operating system.
 12. The non-transitorycomputer readable storage medium of claim 9, wherein enabling the lowpower mode includes: setting a low power mode flag before initiating thebooting process; storing a local time offset; and storing an alarm time.13. The non-transitory computer readable storage medium of claim 12, themethod further comprising, in the low power mode: obtaining a currenttime; applying the local time offset to the current time to obtain alocal time; and displaying the local time.
 14. The non-transitorycomputer readable storage medium of claim 12, the method furthercomprising, in the low power mode: determining that a current time isthe alarm time; and in accordance with a determination that the currenttime is the alarm time, playing an alarm sound.
 15. The non-transitorycomputer readable storage medium of claim 9, wherein the secondthreshold is different from the first threshold.
 16. The non-transitorycomputer readable storage medium of claim 9, the method furthercomprising: in the low power mode, obtaining a third characteristic ofthe battery; determining that the third characteristic is lower than athird threshold; and in accordance with a determination that the thirdcharacteristic is lower than the third threshold, powering off thedevice.
 17. An electronic device, comprising: one or more processors;memory; a battery; and one or more programs, wherein the one or moreprograms are stored in the memory and configured to be executed by theone or more processors, which when executed by the one or moreprocessors, cause the electronic device to perform a method comprising:obtaining a first characteristic of the battery; determining that thefirst characteristic is lower than a first threshold; in accordance witha determination that the first characteristic is lower than the firstthreshold, enabling a low power mode; initiating a booting process;obtaining a second characteristic of the battery; determining whetherthe second characteristic is lower than a second threshold; inaccordance with a determination that the second characteristic is lowerthan the second threshold, continuing the booting process according tothe low power mode; and in accordance with a determination that thesecond characteristic is higher than the second threshold, continuingthe booting process according to a high power mode.
 18. The electronicdevice of claim 17, the method further comprising: in the low powermode, only powering on a subset of modules of the electronic device; andin the high power mode, powering on the subset of modules of theelectronic device and powering on one or more additional modules of theelectronic device.
 19. The electronic device of claim 17, the methodfurther comprising: in the high power mode, invoking a first operatingsystem having a plurality of functionalities; and in the low power mode,invoking a second operating system having only a subset of the pluralityof functionalities of the first operating system.
 20. The electronicdevice of claim 17, wherein enabling the low power mode includes:setting a low power mode flag before initiating the booting process;storing a local time offset; and storing an alarm time.